Craftsman 1/2HP Garage Door Opener 139.53515SR - Manual (Page 7)

Assembly
STEP 2
Install Trolley
AS A TEMPORARY STOP, INSERT A SCREWDRIVER
INTO HOLE IN FRONT END OF TEE RAIL AS SHOWN.
1. Attach threaded shaft to trolley with lockwasher and n uts
as shown.
2. Slide trolley assembly along rail to screwdriver stop.
NOTE: If trolley hits against the nut on Tee rail, center
section was attached from wrong side and must be
repositioned. Review Step 1.
Trolley
Temporary Stop
Screwdriver
Outer Nut
5/16'
Lock Waalner
5/16*
Inner Nut
5/16*
STEP 3
Attach Tee Rail To Opener Chassis
A
USE ONLY THOSE SCREWS MOUNTED IN
TOP OF OPENER CHASSIS. FAILURE TO DO
SO WILL CAUSE SERIOUS DAMAGE TO THE
OPENER.
Washered Screw
5/16"-18x1/2*
PROCEDURE: Place the opener chassis on packing
material to protect the cover. For convenience, place a
support under the cable pulley bracket.
Remove 5/16'-18 x 1/2' washered screws mounted in top
of opener chassis. Align hoies in back end of Tee rail with
holes in opener chassis. Fasten the raii to the chassis
with washered screws previously removed. CAUTION:
USE ONLY THESE SCREWS! Use of any other screws
will cause serious damage to door opener. Tighten
screws secureiy.
insert a 5/16'-16 X 7/8' hex screw into trolley stop hole in
the Tee rail as shown. Tighten securely with a 5/16* lock-
washer and nut.
Hex Screw
5/16*-18x7/8'
Trolley
Stop Hole
Tee Rail
(Back Section)